package com.bank.backend.interceptor;

import com.bank.backend.config.JwtProperties;
import com.bank.backend.mapper.UserMapper;
import com.bank.backend.model.entity.User;
import com.bank.backend.utils.JwtUtil;
import com.bank.backend.utils.UserHolder;
import io.jsonwebtoken.Claims;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * jwt令牌校验的拦截器 - 用户
 */
@Component
@Slf4j
public class JwtTokenUserInterceptor implements HandlerInterceptor {

    @Autowired
    private JwtProperties jwtProperties;
    
    @Resource
    private UserMapper userMapper;

    /**
     * 校验jwt
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //判断当前拦截到的是Controller的方法还是其他资源
        if (!(handler instanceof HandlerMethod)) {
            //当前拦截到的不是动态方法，直接放行
            return true;
        }

        //1、从请求头中获取令牌
        String token = request.getHeader(jwtProperties.getTokenName());

        //2、校验令牌
        try {
            log.info("用户jwt校验:{}", token);
            Claims claims = JwtUtil.parseJWT(jwtProperties.getSecretKey(), token);
            Integer userId = (Integer) claims.get("userId");
            Boolean isAdmin = (Boolean) claims.get("isAdmin");
            
            // 验证用户是否存在
            if (userId == null) {
                response.setStatus(401);
                return false;
            }
            
            // 设置用户信息到ThreadLocal
            UserHolder.setUserId(userId);
            UserHolder.setIsAdmin(isAdmin);
            
            // 同时设置完整的User对象
            User user = userMapper.selectById(userId);
            if (user != null) {
                UserHolder.saveUser(user);
            }
            
            log.info("当前用户id：{}", userId);
            //3、通过，放行
            return true;
        } catch (Exception ex) {
            //4、不通过，响应401状态码
            response.setStatus(401);
            return false;
        }
    }
    
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) {
        // 请求结束后，清除 ThreadLocal 中的用户信息
        UserHolder.removeUser();
    }
} 